1. Field of the Invention
The present invention relates to an electronic timepiece having a function of converting and displaying an average rate obtained by a logical regulation within a short period of time, the logical regulation being carried out in a period longer than a logical regulation period which is generally employed.
2. Description of the Prior Art
The regulation resolving power of temperature-compensated electronic timepieces is required to be an exceedingly small value, that is 4 ms/d or 8 ms/d, in order to realize high precision.
To achieve such resolving power by means of a logical regulator, the operating period of the logical regulator must be 640 seconds or 320 seconds.
However, since the maximum time which can be measured with conventional measuring devices which are obtainable on the market has heretofore been 10 seconds, no regulation which involves a resolving power of 4 ms/d cannot be effected by a logical regulator.
Accordingly, it is conventional practice to adopt, for example, a method wherein the load capacity of an oscillator circuit is switched.
The above-described method in which an oscillator circuit is directly actuated has the disadvantages that oscillating characteristics are undesirably changed to a substantial extent and that it is necessary to additionally carry out an operation of adjusting the amount of regulation when the oscillator circuit is actuated. In addition, since an analog quantity is handled to adjust the amount of regulation, errors are readily generated in adjustment, and it is therefore impossible to effect temperature compensation of high precision.